Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Atomic Nuclei: Nuclear Relaxation Processes01:23

Atomic Nuclei: Nuclear Relaxation Processes

1.4K
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis,  the precessing magnetic moments are randomly oriented around the z-axis.
1.4K
Atomic Nuclei: Magnetic Resonance01:05

Atomic Nuclei: Magnetic Resonance

1.4K
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
1.4K
Colors and Magnetism03:02

Colors and Magnetism

14.5K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
14.5K
Atomic Nuclei: Types of Nuclear Relaxation01:28

Atomic Nuclei: Types of Nuclear Relaxation

1.1K
Nuclear relaxation restores the equilibrium population imbalance and can occur via spin–lattice or spin–spin mechanisms, which are first-order exponential decay processes.
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers...
1.1K
Other Unique Bacteria01:18

Other Unique Bacteria

534
Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic...
534
Atomic Nuclei: Nuclear Spin State Overview01:03

Atomic Nuclei: Nuclear Spin State Overview

2.2K
NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of one, the...
2.2K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Quantum Zeno Effect Permits Magnetosensitivity in Lipid Peroxidation despite Fluctuating Inter-Radical Coupling.

JACS Au·2026
Same author

Detection of the Carcinogen Benzo[<i>a</i>]pyrene through Photochemically Induced Dynamic Nuclear Polarization: Linking Liquid-State <sup>1</sup>H NMR with Spatially Resolved Imaging.

Analytical chemistry·2026
Same author

Reaction-yield detected magnetic resonance spectroscopy of radical pairs in cryptochrome-4a: a computational study.

Free radical biology & medicine·2026
Same author

Conformational Switching Controls Biradical Spin Dynamics in Flavin-Tryptophan Dyads.

Journal of the American Chemical Society·2026
Same author

A hybrid compass mechanism combining radical pairs and magnetite crystals.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

A Charge-Reversal Point Mutation Completely Depletes Flavin Chromophore from European Robin Cryptochrome 4a Protein.

The journal of physical chemistry letters·2026
Same journal

Lower bound of the capacitance of constant phase elements based on electrochemical impedance spectra.

Physical chemistry chemical physics : PCCP·2026
Same journal

Stability constants of lanthanide-nitrate complexes in aqueous solutions: a theoretical study.

Physical chemistry chemical physics : PCCP·2026
Same journal

Lead-free Cs<sub>3</sub>MnCl<sub>5</sub> and CsMnCl<sub>3</sub> crystals: rapid on-chip crystallization, phase transition and fluorescence sensing applications.

Physical chemistry chemical physics : PCCP·2026
Same journal

F-Interstitial passivation preserves host-like optoelectronic properties in <sup>229</sup>Th:YLF nuclear-clock platforms.

Physical chemistry chemical physics : PCCP·2026
Same journal

Structural trends of tryptophan dimer: hydrogen bonding <i>versus</i> π-stacking from an energy decomposition analysis perspective.

Physical chemistry chemical physics : PCCP·2026
Same journal

Achieving high thermoelectric performance in Sb<sub>2</sub>Se<sub>3</sub>-alloyed GeTe through synergistic optimization of electrical and thermal transport.

Physical chemistry chemical physics : PCCP·2026
See all related articles

Related Experiment Video

Updated: Mar 23, 2026

Magnetic Resonance Spectroscopy of live Drosophila melanogaster using Magic Angle Spinning
07:33

Magnetic Resonance Spectroscopy of live Drosophila melanogaster using Magic Angle Spinning

Published on: April 15, 2010

13.0K

Electron spin relaxation in cryptochrome-based magnetoreception.

Daniel R Kattnig1, Ilia A Solov'yov, P J Hore

  • 1Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, OX1 3QZ, UK. peter.hore@chem.ox.ac.uk.

Physical Chemistry Chemical Physics : PCCP
|March 30, 2016
PubMed
Summary
This summary is machine-generated.

Migratory birds may use cryptochrome proteins for magnetic sense. Spin relaxation in these proteins is crucial for quantum dynamics, but isolated cryptochromes may not fully support this avian compass mechanism.

More Related Videos

Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
08:01

Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures

Published on: November 21, 2019

7.8K
Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments
09:25

Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments

Published on: November 1, 2024

2.9K

Related Experiment Videos

Last Updated: Mar 23, 2026

Magnetic Resonance Spectroscopy of live Drosophila melanogaster using Magic Angle Spinning
07:33

Magnetic Resonance Spectroscopy of live Drosophila melanogaster using Magic Angle Spinning

Published on: April 15, 2010

13.0K
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
08:01

Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures

Published on: November 21, 2019

7.8K
Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments
09:25

Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments

Published on: November 1, 2024

2.9K

Area of Science:

  • Biophysics
  • Quantum Biology
  • Avian Navigation

Background:

  • The magnetic compass sense in migratory birds is hypothesized to involve photochemically formed radical pairs within cryptochrome proteins.
  • This mechanism requires slow electron spin relaxation for quantum coherence to interact with Earth's magnetic field.

Purpose of the Study:

  • To investigate the impact of spin relaxation on the function of cryptochrome proteins as magnetic compass sensors.
  • To assess whether isolated cryptochromes, like Arabidopsis thaliana cryptochrome 1 (AtCry1), can support the necessary quantum dynamics for avian navigation.

Main Methods:

  • Utilized all-atom molecular dynamics simulations.
  • Applied Bloch-Redfield relaxation theory and spin dynamics calculations.
  • Studied both flavin-tryptophan and flavin-Z˙ radical pairs within a model cryptochrome.

Main Results:

  • Optimal radical pair lifetimes for spin relaxation in AtCry1 are on the order of microseconds.
  • Flavin-Z˙ radical pairs are less susceptible to relaxation than flavin-tryptophan pairs.
  • Spin relaxation in isolated AtCry1 is inconsistent with the long coherence times needed to explain disruptions by radiofrequency fields.

Conclusions:

  • Isolated AtCry1 exhibits spin relaxation properties that may be incompatible with the requirements of the avian magnetic compass.
  • A functional in vivo cryptochrome sensor likely possesses different dynamic or structural properties compared to isolated AtCry1.
  • The study highlights limitations of the current hypothesis and advances understanding of radical pair magnetic sensors in biological systems.